P FEBl 
AMERICAN Mfiffi 
JOURNAL OF BOTANY 
Vol. IV February, 19 17 No. 2 
FIFTEEN- AND SIXTEEN-CHROMOSOME OENOTHERA 
MUTANTS! 
Anne M. Lutz 
A. Introduction 
The present communication is the second of a series of three, the 
first having been published in a preceding issue of this Journal^ under 
the head of "Mutants of Oenothera with diminutive chromosomes." 
The three papers embody a portion of the results derived from a 
prolonged study of the Lamarckiana group of Oenothera conducted at 
the Station for Experimental Evolution^ (1907-1911), at the University 
of Louvain in Professor V. Gregoire's laboratory (1911-1912), and 
later in consultation with Professor Gregoire by letter (1912-1914). 
As stated in the first report of the series, the primary object of these 
communications is to discuss, in the light of the Cold Spring Harbor 
and Louvain studies, certain theories and conclusions which Gates 
has given out from time to time and which Gates and Miss Thomas 
('14) have based upon the results of their investigations. 
The first paper described an interesting condition found in two 
mutant types produced by 15-chromosome 0. lata X 14-chromosome 
0. Lamarckiana; one, a new form, 0. aberrans, grown at Cold Spring 
Harbor in 1908 and 1909, and the other, 0. mbrinervis, grown at Am- 
sterdam in 1 91 2. The somatic cells of these three plants were shown 
1 Briefly reported in a paper read before the Botanical Society of America, 
December 29, 1915, and in a preliminary note published in Science (Lutz, 'i6a) 
entitled "The production of i4+-chromosome mutants by 14-chromosome Oenothera 
Lamarckiana.'' 
^Amer. Journ. Bot. 3: 502-526. 1916. 
' Maintained by the Carnegie Institution of Washington until March, 191 1. 
[The Journal for January (4: 1-52) was issued Feb. 3, 191 7.] 
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